1. Field of Disclosure
The present disclosure relates to an identifying method and device for detecting a specific region of a translucent medium. More particularly, the present disclosure relates to an identifying method and device for detecting a specific region of a translucent medium based on a self comparison result of a light sensing intensity sensed at one time instant.
2. Description of Related Art
Due to the light transmission character of a translucent medium, such as a translucent card or a translucent slide, it is not easy for a sensing machine to distinguish whether the translucent medium has passed, and even more, the sensing machine cannot detect a relative position of the translucent medium. In order to allow the sensing machine to be able to detect the translucent medium, a light-shielding pattern layer or infrared transmission ink is disposed at a specific position of the translucent medium according to the prior art method so as to assist the sensing machine in detecting the specific position of the translucent medium even when the translucent medium is moving.
In addition, another prior art method is to compare signals respectively detected at different time points by the light sensor under the circumstances that the translucent medium is moving so as to serve as a judgment basis for the specific position (such as an edge of the translucent medium) of the translucent medium.
However, the translucent medium that satisfies the specifications is required to be manufactured according to the above methods, and the above methods need to cooperate with an additional signal amplifier and digital/analog conversion circuit. Not only is the acquisition cost of sensing machine increased, but the manufacturing cost of the translucent medium is also increased.
For the forgoing reasons, there is a need to solve the above-mentioned inconveniences and shortcomings by providing an identifying method and device for detecting a specific region of a translucent medium, which is also an objective that the relevant industry is eager to achieve.